The profound symptom burden associated with advanced lung cancer (LC) makes caregiving a complex and burdensome task. Despite the input of outpatient palliative care services, LC families are often unprepared for caregiving, have low self-efficacy for managing symptoms at home, report high rates of physical and emotional distress, and receive very little skills training or psychosocial care. To date, the few psychosocil intervention trials targeting the caregivers of advanced cancer patients that have been conducted have mostly targeted the families of hospice patients, have not been well-integrated into routine palliative care, and have not addressed the specific needs of LC caregivers. Based on our published and recently completed pilot work in LC, we have developed a psychosocial intervention called CareSTEPS (self-Care, Stress management, sympTom management, Effective communication, Problem-solving, and Social support). CareSTEPS is grounded by Self Determination Theory (SDT) which focuses on individuals' needs for developing autonomy (a sense of choice and volition), competence (self-efficacy), and relatedness (a sense of belonging and connection). It: 1) teaches skills to enhance caregiver competence for managing symptoms, practicing self-care, and coping with cancer~ 2) supports caregiver autonomy by providing a clear rationale for recommendations and a variety of options to encourage choice and elaboration~ and, 3) seeks to improve caregivers' sense of relatedness by teaching strategies for effective communication and soliciting/accepting social support. We will enroll 200 LC patients within one month of treatment initiation (baseline) and their caregivers and randomize them to either a usual medical care (UMC) condition or the CareSTEPS intervention (caregivers receive a manual and six 45-minute weekly counseling sessions by telephone). Follow-up surveys are completed at 8 weeks and 6 months post-baseline. The primary aim is to determine the impact of the CareSTEPS intervention on caregiver self-care behaviors, physical and emotional QOL, and satisfaction with care. Secondary aims are to: 1a) examine the effects of CareSTEPS on the SDT constructs of competence, autonomy, and relatedness~ 1b) test whether caregiver competence, autonomy and relatedness mediate the effects of CareSTEPS on caregiver outcomes as hypothesized~ 2) explore whether sociodemographic, medical, and relationship factors moderate the effects of the CareSTEPS intervention on SDT constructs~ and, 3) explore the effects of CareSTEPS on patient QOL, palliative care utilization, nd satisfaction with care. CareSTEPS fills an important service gap by providing education, skills training, and support to the caregivers of advanced LC patients who are on active treatment. The home-based delivery format will facilitate future dissemination and outreach. By empowering families with the skills they need to provide care and meet the challenges of LC, CareSTEPS holds great promise for improving caregiver QOL, patient QOL, and the quality of palliative/supportive care services for advanced cancer patients and their families.